title: Different effectiveness of subthalamic deep brain stimulation in Parkinson's disease: A comparative cohort study at 1 year and 5 years.
abstract: OBJECTIVE
  Subthalamic nucleus deep brain stimulation (STN-DBS) has been shown to produce long-term symptom improvement in Parkinson's disease. The aim of this study was to identify the target symptoms that show the most improvement at 1 year and at 5 years after STN-DBS.
  
  
  METHODS
  This was a 5-year cohort study of 41 consecutive patients treated with bilateral STN-DBS. Clinical evaluations were performed 1 month prior to surgery and 1 year and 5 years after surgery. The outcome measurements at 1 year and 5 years were the changes compared with the baseline in Unified Parkinson's Disease Rating Scale (UPDRS) parts I, II, III, and IV scores, the Hoehn and Yahr stage, and Schwab and England Activities of Daily Living (SEADL) scores in the conditions of off-medication/on-stimulation and off-medication/off-stimulation. Further analysis included changes in the levodopa equivalent daily dose.
  
  
  RESULTS
  When compared to the preoperative baseline off-medication condition, significant improvements were observed in the UPDRS parts I, II, III, and IV and SEADL (p < 0.001) scores in the off-medication/on-stimulation condition 1 year after STN-DBS. Five years after STN-DBS, improvements in UPDRS scores were observed only for parts II, III, and IV (p < 0.001). In the off-medication/off-stimulation condition, no significant improvement was observed. At 5 years, significant deteriorations were observed in scores for the UPDRS part III axial subitem (p = 0.005), UPDRS part I (p = 0.005), UPDRS part II (p < 0.001), and SEADL (p = 0.001).
  
  
  CONCLUSIONS
  The long-term effect of STN-DBS on motor function is promising, although the magnitude of its effectiveness varied over the 5-year period.
authors.affiliation: Department of Nursing, Tzu Chi University, Hualien, Taiwan; Institute of Medical Sciences, Tzu Chi University, Hualien, Taiwan.
authors.forename: Jiin-Ling
authors.initials: JL
authors.lastname: Jiang
authors.affiliation: Institute of Medical Sciences, Tzu Chi University, Hualien, Taiwan; Department of Neurosurgery, Tzu Chi General Hospital, Hualien, Taiwan; Department of Surgery, Tzu Chi University, Hualien, Taiwan; Parkinson's Clinical and Research Center, Tzu Chi General Hospital, Hualien, Taiwan.
authors.forename: Shin-Yuan
authors.initials: SY
authors.lastname: Chen
authors.affiliation: Institute of Medical Sciences, Tzu Chi University, Hualien, Taiwan.
authors.forename: Tsung-Cheng
authors.initials: TC
authors.lastname: Hsieh
authors.affiliation: Department of Neurosurgery, Tzu Chi General Hospital, Hualien, Taiwan; Department of Surgery, Tzu Chi University, Hualien, Taiwan.
authors.forename: Chi-Wei
authors.initials: CW
authors.lastname: Lee
authors.affiliation: Department of Neurology, Tzu Chi General Hospital, Hualien, Taiwan.
authors.forename: Sheng-Huang
authors.initials: SH
authors.lastname: Lin
authors.affiliation: Department of Neurosurgery, Tzu Chi General Hospital, Hualien, Taiwan; Department of Surgery, Tzu Chi University, Hualien, Taiwan; Parkinson's Clinical and Research Center, Tzu Chi General Hospital, Hualien, Taiwan. Electronic address: flydream.tsai@gmail.com.
authors.forename: Sheng-Tzung
authors.initials: ST
authors.lastname: Tsai
mesh_terms: D000203:Activities of Daily Living; D000328:Adult; D046690:Deep Brain Stimulation / Q000379:methods*; D005260:Female; D006801:Humans; D008137:Longitudinal Studies; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D010300:Parkinson Disease / Q000628:therapy*; D011446:Prospective Studies; D012720:Severity of Illness Index; D020531:Subthalamic Nucleus / Q000503:physiopathology*; D013624:Taiwan; D014057:Tomography, X-Ray Computed; D016896:Treatment Outcome
keywords: Parkinson's disease; deep brain stimulation; long-term